Patent GB-271628-A (GB)
Title: Improvements in or relating to control apparatus for mine cage winding or hoisting machinery
IPC: B66B5/08
Filed: 1926-05-05
Abstract: 271,628. Vickers, Ltd., and Bishop, A. V. May 5, 1926. Emergency power cutoff gear; stopping automatically at end of run ; regulating and controltransmitting gear ; indicating apparatus.-In control apparatus for mine cage machinery of the kind in which on the occurrence of overwinding or overspeeding the brakes are operated by a weight released by the movement of a nut on a screwed spindle rotating with the winding gear or by a centrifugal governor, the nut or governor is adapted to open a switch in the circuit of the emergency solenoid normally provided for the purpose of applying the brake or otherwise bringing to rest the winding gear. An indicator is provided adjacent to the depth indicator and moves in advance of, or lags behind it, according as the speed of winding is above or below the normal. A threaded spindle 1, Fig. 1, driven from the hoisting mechanism carries a nut 2 and drives a centrifugal governor 3. At the ends of its travel the nut engages and tilts a pivoted plate 4 or pivoted arm 6 which are connected by a link 7. The plate 4 is connected by toggle links 11 and a link 10 to a switch in the circuit of a solenoid which when actuated causes the application of the brake. If overspeeding occurs a pin 8 mounted on the sliding collar of the governor moves along a slot 9 and tilts the plate. By varying the relative inclination of the links 11, the switch can be actuated at different degrees of overwind or overspeed. The nut 2 actuates also a series of interconnected cams 14, 15. One cam 15 is connected by links 20, 21, 23 to a pivoted arm 24 which when rocked actuates the brake mechanism. This arm is engaged by a pin 26 on a link 27 pivoted to the brake lever 19. A pair of cams 14 is connected by links 29, bellcrank levers 30, and links 31 to the controlling lever 28 of the hoisting motor. These cams restore the lever to the neutral position at the end of the run if the attendant has omitted to do so, and also control the rate at which the lever can be moved from neutral position towards either of the driving positions. Another cam 15 is connected by a link 32 to means which applies the brake at an abnormally rapid rate in the event of overwinding. The cams 14, 15 may be adjustable in the vertical direction in order to provide additional means for varying the operation in accordance with the nature of the load, or to permit the adjustment necessary for winding to or from different levels. The brackets in which the cams are pivoted may be moved towards or away from each other by a right or left handed screw. Prefera.bly the bracket 33 carrying the cams 15 is locked in various positions in a vertical guide. and the pivot of the lever 17 used in the linkage connecting the cams 14, 15 is carried by a lever 34 pivoted at 35 and connected by a link 36 to a lever 37 which is pivoted at 38 and connected by pin-and-slot mechanism to the bracket 33. The depth indicator 39 is driven by a shaft 41 which also drives through gears 47, 48 a centrifugal governor 50 and through the gears 47 the driving member 51 of a pair of expanding pulleys. The driven pulley member 52 is mounted on a sleeve which is free on the shaft 41 and drives through gears 46 and a clutch 45 the spindle 44 on which the indicator 43 is mounted. The effective diameters of the pulleys 51, 52 are determined by levers 53 pivoted at 54 and engaging grooved collars attached to the pulleys. The levers 53 are connected by links 56 to the piston 55 of a servomotor operated by fluid admitted through a port 57. The valve 58 controlling the port is controlled by the governor 50 The nut 39 engages skates 60 near the ends of its travel and disengages the clutch 45. Specification 274,554 is referred to.